Active Site

Thymidylate synthase, active site (IPR020940)

Short name: Thymidylate_synthase_AS


Thymidylate synthase (EC: [PMID: 6996564, PMID: 2117882] catalyzes the reductive methylation of dUMP to dTMP with concomitant conversion of 5,10-methylenetetrahydrofolate to dihydrofolate: 5,10-methylenetetrahydrofolate + dUMP = dihydrofolate + dTMP This provides the sole de novo pathway for production of dTMP and is the only enzyme in folate metabolism in which the 5,10-methylenetetrahydrofolate is oxidised during one-carbon transfer [PMID: 3099389]. The enzyme is essential for regulating the balanced supply of the 4 DNA precursors in normal DNA replication: defects in the enzyme activity affecting the regulation process cause various biological and genetic abnormalities, such as thymineless death [PMID: 2243092]. The enzyme is an important target for certain chemotherapeutic drugs. Thymidylate synthase is an enzyme of about 30 to 35 Kd in most species except in protozoan and plants where it exists as a bifunctional enzyme that includes a dihydrofolate reductase domain [PMID: 3099389]. A cysteine residue is involved in the catalytic mechanism (it covalently binds the 5,6-dihydro-dUMP intermediate). The sequence around the active site of this enzyme is conserved from phages to vertebrates.

GO terms

Biological Process

GO:0006231 dTMP biosynthetic process

Molecular Function

GO:0004799 thymidylate synthase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns